Oklahoma Severe Weather Discussion - May 2011

[Thunder]

http://www.spc.noaa.gov/products/out...0523_1630.html

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1127 AM CDT MON MAY 23 2011

VALID 231630Z - 241200Z

...THERE IS A MDT RISK OF SVR TSTMS ACROSS PORTIONS OF WESTERN AND
NORTHERN OK...SOUTHEAST KS...AND SOUTHWEST MO...

...THERE IS A SLGT RISK OF SVR TSTMS OVER A LARGE AREA FROM THE
SOUTHERN PLAINS...ACROSS THE MID MS AND OH VALLEYS...INTO NY/PA AND
THE MID ATLANTIC REGION...

A VERY COMPLEX CONVECTIVE DAY IS FORECAST ACROSS THE UNITED STATES
TODAY...WITH NUMEROUS AREAS OF SEVERE WEATHER POTENTIAL.

...CENTRAL/SOUTHERN PLAINS...
ISOLATED THUNDERSTORMS HAVE DEVELOPED NEAR DFW TODAY...AND ARE
EXPECTED TO TRACK EASTWARD THROUGH THE DAY WITH A CONTINUED RISK OF
ISOLATED SEVERE WEATHER. BEHIND THIS ACTIVITY...STRONG HEATING AND
DEWPOINTS IN THE UPPER 60S TO LOWER 70S WILL YIELD AFTERNOON MLCAPE
VALUES OF 4000-5000 J/KG AND A WEAK CAP. A SHORTWAVE TROUGH MOVING
ACROSS WEST TX WILL LIKELY RESULT IN THE DEVELOPMENT A FEW DISCRETE
SUPERCELL THUNDERSTORMS BY MID AFTERNOON OVER WESTERN OK. STORMS
WILL ALSO LIKELY DEVELOP BY EARLY EVENING IN VICINITY OF REMNANT
OUTFLOW BOUNDARIES OVER NORTHERN OK/SOUTHERN KS. BACKING LOW LEVEL
FLOW THROUGH THE EVENING WILL PROMOTE UPDRAFT ROTATION WITH RISK OF
VERY LARGE HAIL AND A FEW TORNADOES THROUGH THE EVENING.
OVERNIGHT... GENERAL MODEL CONCENSUS SUGGESTS STORMS MAY GROW
UPSCALE OVERNIGHT WITH AN MCS TRACKING TO AR WITH A RISK OF HAIL AND
DAMAGING WINDS.

[Jesseda]

so mister Thunder, r u taking over ventures job? jk.. I hope we dont get anything like joplin, but i do hope something takes my lemon of a car and mangles it, i really want a different car, My car isnt that old but has problems like very 6 months sincei have bought it!

[Thunder]

I am his assistant.

[venture]

I am his assistant.

Call me shocked. :-P

Anyway. Initiation should be taking place in about 2-3 hours across western OK. Storms will probably be nearing the Metro are by 5-7PM.

[Thunder]

I love you, too.

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NORMAN OK
1155 AM CDT MON MAY 23 2011

OKZ004>048-050>052-TXZ083>090-231700-
HARPER-WOODS-ALFALFA-GRANT-KAY-ELLIS-WOODWARD-MAJOR-GARFIELD-NOBLE-
ROGER MILLS-DEWEY-CUSTER-BLAINE-KINGFISHER-LOGAN-PAYNE-BECKHAM-
WA****A-CADDO-CANADIAN-OKLAHOMA-LINCOLN-GRADY-MCCLAIN-CLEVELAND-
POTTAWATOMIE-SEMINOLE-HUGHES-HARMON-GREER-KIOWA-JACKSON-TILLMAN-
COMANCHE-STEPHENS-GARVIN-MURRAY-PONTOTOC-COAL-COTTON-JEFFERSON-
CARTER-JOHNSTON-ATOKA-LOVE-MARSHALL-BRYAN-HARDEMAN-FOARD-WILBARGER-
WICHITA-KNOX-BAYLOR-ARCHER-CLAY-
1155 AM CDT MON MAY 23 2011

THIS HAZARDOUS WEATHER OUTLOOK COVERS NORTHERN...WESTERN...
CENTRAL...AND SOUTHERN OKLAHOMA...AND WESTERN NORTH TEXAS.

.DAY ONE...TODAY AND TONIGHT...

THUNDERSTORM OUTLOOK...
THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
CENTRAL AND WESTERN OKLAHOMA. THERE IS A SLIGHT RISK OF SEVERE
THUNDERSTORMS ACROSS MUCH OF THE REMAINDER OF OKLAHOMA AND WESTERN
NORTH TEXAS.

LOCATION...
THE MODERATE RISK IS EAST OF A WOODWARD TO ALTUS LINE...AND NORTH OF
A FREDERICK TO WAURIKA TO HOLDENVILLE LINE. THE SLIGHT RISK IS SOUTH
AND WEST OF THE MODERATE RISK ACROSS THE REMAINDER OF OKLAHOMA AND
WESTERN NORTH TEXAS.

IMPACTS...DAMAGE TO HOMES...CARS AND VEGETATION POSSIBLE FROM HAIL
TO THE SIZE OF BASEBALLS AND DAMAGING WIND GUSTS OVER 65 MPH.

TIMING...
THE MOST LIKELY TIME FOR SEVERE WEATHER WILL BE THIS AFTERNOON AND
EVENING... ALTHOUGH THE RISK OF SEVERE WEATHER WILL CONTINUE
OVERNIGHT.

RECOMMENDED ACTIONS...
STORM SPOTTER GROUPS AND EMERGENCY MANAGEMENT PERSONNEL ACROSS THE
RISK AREA SHOULD PLAN FOR THE POTENTIAL OF SEVERE WEATHER OPERATIONS
THIS AFTERNOON THROUGH THE OVERNIGHT HOURS.

DISCUSSION...
A DRYLINE ACROSS THE OKLAHOMA AND TEXAS PANHANDLE WILL MOVE TO NEAR
THE BORDER OF WESTERN OKLAHOMA AND THE TEXAS PANHANDLE THIS
AFTERNOON. MEANWHILE...A COLD FRONT WILL BECOME STATIONARY ACROSS
NORTHWEST OKLAHOMA...WHILE AN OUTFLOW BOUNDARY FROM STORMS IN
NORTHEAST OKLAHOMA REMAINS IN NORTH CENTRAL OKLAHOMA. THUNDERSTORMS
WILL LIKELY DEVELOP THIS AFTERNOON... ESPECIALLY NEAR THE FRONT
AND OUTFLOW BOUNDARY IN THE NORTH... WITH OTHER STORMS POTENTIALLY
DEVELOPING NEAR THE DRYLINE ACROSS WESTERN OKLAHOMA AND WESTERN
NORTH TEXAS. OTHER ISOLATED STORMS MAY DEVELOP ELSEWHERE ACROSS THE
AREA THIS AFTERNOON AND EVENING. THE ATMOSPHERE WILL ONCE AGAIN
BE VERY UNSTABLE OVER OKLAHOMA AND NORTH TEXAS AND WILL SUPPORT
SUPERCELLS CAPABLE OF PRODUCING HAIL LARGER THAN BASEBALLS...
DAMAGING WINDS OVER 65 MPH... AND ISOLATED TORNADOES. STORMS WILL
LIKELY BECOME MORE WIDESPREAD THIS EVENING AS THEY MOVE EASTWARD
ACROSS OKLAHOMA AND NORTH TEXAS WITH THE CONTINUED POTENTIAL FOR
SCATTERED SEVERE THUNDERSTORMS.

PROBABILITY TABLE...
VALID THROUGH 700 AM CDT TUESDAY MAY 24.
PROBABILITY OF THUNDERSTORMS OCCURRING IN THE
NWS NORMAN COUNTY WARNING AREA...80 PERCENT.
PROBABILITY OF SEVERE STORMS IF STORMS OCCUR...100 PERCENT.

Tomorrow and onward...

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY...

THUNDERSTORM OUTLOOK...
THERE IS A POTENTIAL FOR MORE WIDESPREAD AND SIGNIFICANT SEVERE
WEATHER ON TUESDAY...ESPECIALLY NEAR AND EAST OF INTERSTATE 35 WHERE
THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS. SEVERE STORMS ARE
EXPECTED TO DEVELOP BY AFTERNOON AS A STRONG UPPER SYSTEM LIFTS
NORTHEASTWARD FROM THE SOUTHERN ROCKIES AND INTERACTS WITH A
STRENGTHENING DRYLINE PUSHING INTO OKLAHOMA AND WESTERN NORTH TEXAS.
VERY LARGE HAI...DAMAGING WINDS...AND TORNADOES WILL BE POSSIBLE.
THUNDERSTORM CHANCES CONTINUE WEDNESDAY AND WEDNESDAY NIGHT ALTHOUGH
THE RISK OF SEVERE WEATHER WILL LIKELY MOVE EAST OF THE AREA.

[Thunder]

Tomorrow, a new SPC (or discussion) just came out with possible upgrade...

TORNADIC OUTBREAK POSSIBLE ACROSS THE CENTRAL AND SOUTHERN PLAINS TUESDAY. AN UPGRADE TO HIGH RISK MAY BE WARRANTED AS SITUATION BECOMES MORE CERTAIN...

[megax11]

I don't see it happening.

First off, I have always thought the weathermen here are full of crap and overdramatise things, as if they're hard up for action. I just watched the weather and they showed their predictor, which already seems to be wrong.

Second off, I don't think tornadoes can hit certain parts of OKC. The part I refer to is the inner ring of the OKC metro. I've been right all these years, and I don't myself being proven wrong anytime soon.

The inner ring I consist of is the square area surrounded by I-44, I-40, I-35, and I-240.

I just don't see much happening today.

[venture]

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1216 PM CDT MON MAY 23 2011

VALID 241200Z - 251200Z

...THERE IS A MDT RISK OF SVR TSTMS FROM NWRN TX TO SRN NEB...

...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK OVER
THE SRN/CNTRL PLAINS THROUGH THE OH/TN VALLEY TO SRN NY...

...TORNADIC OUTBREAK POSSIBLE ACROSS THE CENTRAL AND SOUTHERN PLAINS
TUESDAY. AN UPGRADE TO HIGH RISK MAY BE WARRANTED AS SITUATION
BECOMES MORE CERTAIN...

A CLASSIC PLAINS TORNADIC OUTBREAK APPEARS TO BE EVOLVING ACROSS THE
CNTRL/SRN PLAINS...ESPECIALLY FOR KANSAS AND OKLAHOMA. LATEST MODEL
GUIDANCE IS CONSISTENT REGARDING THE PROGRESSION OF A VERY STRONG
MID LEVEL SHORTWAVE TROUGH...CURRENTLY DIGGING ESEWD ACROSS SRN
CA...INTO THE SWRN U.S./SRN ROCKIES BEFORE EJECTING INTO THE PLAINS
BY PEAK HEATING. A VERY DIFFLUENT UPPER FLOW REGIME WILL OVERSPREAD
THE PLAINS AS 30-60M 12HR HEIGHT FALLS EDGE EWD. ADDITIONALLY...H5
SPEED MAX APPROACHING 80-90KT...AS NOTED IN THE GFS...WILL RACE TO A
POSITION OVER NWRN TX/SWRN OK BY 25/00Z WHICH WILL GENERATE VERY
STRONG SHEAR ACROSS THE WARM SECTOR FOR AREAS NEAR THE RED RIVER
REGION...NWD INTO KS AND EVEN SRN NEB. NEEDLESS TO SAY A VERY
DYNAMIC SHORTWAVE TROUGH SHOULD TIME FAVORABLY FOR RAPID SEVERE
THUNDERSTORM INITIATION ALONG/AHEAD OF THE DRYLINE AS ATMOSPHERIC
HEATING IS MAXIMIZED.

EARLY IN THE MORNING A FEW THUNDERSTORM CLUSTERS MAY BE ONGOING
WITHIN THE STRONGEST ZONE OF WARM ADVECTION FROM KS EWD INTO MO AND
THE LOWER OH VALLEY. THIS REGION OF ASCENT AND STORMS MAY
TEMPORARILY FORCE A CONVECTIVE OUTFLOW INTO NRN AR...NWWD INTO SRN
KS. HOWEVER...A NWD RETREAT IS LIKELY TO AT LEAST THE I-70 CORRIDOR
IN KS AS DAYTIME HEATING OCCURS ACROSS THE WARM SECTOR. FOR THIS
REASON IT APPEARS A VERY UNSTABLE AIRMASS WILL BE IN PLACE FROM NRN
TX INTO SRN KS WHERE SBCAPE VALUES COULD EXCEED 5000 J/KG WHERE SFC
DEW POINTS HOLD IN THE LOWER 70S. FORECAST SOUNDINGS ACROSS THE
WARM SECTOR EXHIBIT CLASSIC TORNADIC SUPERCELL STRUCTURES WITH
STRONG LOW LEVEL HELICITY ACROSS KS/OK WITH DEEP LAYER SHEAR ON THE
ORDER OF 50-60KT. BY MID AFTERNOON...STRONG HEATING SHOULD BE NOTED
ALONG/WEST OF THE DRYLINE FORCING TEMPERATURES TO SOAR WELL INTO THE
90S...EFFECTIVELY REMOVING INHIBITION FOR CONVECTIVE DEVELOPMENT
WHERE LOW LEVEL CONVERGENCE IS MAXIMIZED. AT THIS TIME IT APPEARS
TSTMS SHOULD INITIATE ALONG THE DRYLINE BY 21Z...ALTHOUGH ACTIVITY
COULD DEVELOP MUCH QUICKER WITHIN THE STRONGER FORCING ACROSS THE
CNTRL HIGH PLAINS TO THE NORTH-EAST OF THE SFC LOW WITHIN STRONGEST
UPSLOPE FLOW.

WHILE DRYLINE SUPERCELLS LIFE CYCLE WILL BE MAXIMIZED BETWEEN
21Z-04Z...STRONG WARM ADVECTION ACROSS THE CNTRL PLAINS SHOULD
MAINTAIN A ZONE OF CONCENTRATED SEVERE NEAR/NORTH OF THE WARM FRONT
ACROSS KS/NEB INTO MO DURING THE OVERNIGHT HOURS.

[Thunder]

megax11, be patience. It takes time for these storms to form and so on. No one is saying anything about a tornado will definitely hit the inner metro ring. Relax. And don't pay much attention to those gadgets they show on television.

[venture]

I don't see it happening.

First off, I have always thought the weathermen here are full of crap and overdramatise things, as if they're hard up for action. I just watched the weather and they showed their predictor, which already seems to be wrong.

Second off, I don't think tornadoes can hit certain parts of OKC. The part I refer to is the inner ring of the OKC metro. I've been right all these years, and I don't myself being proven wrong anytime soon.

The inner ring I consist of is the square area surrounded by I-44, I-40, I-35, and I-240.

I just don't see much happening today.

Luckily the information here isn't from the guys on TV you don't like.

A tornado can hit any part of the city it wants to, it is just a matter of time. People thought for years Norman couldn't be hit, than the EF-4 last year.

[drum4no1]

I don't see it happening.

First off, I have always thought the weathermen here are full of crap and overdramatise things, as if they're hard up for action. I just watched the weather and they showed their predictor, which already seems to be wrong.

Second off, I don't think tornadoes can hit certain parts of OKC. The part I refer to is the inner ring of the OKC metro. I've been right all these years, and I don't myself being proven wrong anytime soon.

The inner ring I consist of is the square area surrounded by I-44, I-40, I-35, and I-240.

I just don't see much happening today.

I work in TV and yes the TV weatherguys do tend to go with the worst case scenario, they do have their reasons and some of them are legitimate. However I tend to believe it when the weatherservice starts talking about it too. IMO they dont have much of a reason to hype..

[BG918]

A lot more clouds than yesterday, esp. east of I-35. If it stays that way it could limit the severity of today's storms.

[Uncle Slayton]

You'd think that with downtown Fort Worth being hit as well as Nashville, that the evidence would disabuse anyone of the notion that they are geographically limited to where they can form. Dallas has been blasted as well a few times in the 50s. Had a great aunt in Dallas who was mortally afraid of tornadoes, that she would die in one. Then, when the one hit Oak Cliff in 1957, she panicked herself into a massive coronary and died. Turns out she was right all along...

[venture]

A lot more clouds than yesterday, esp. east of I-35. If it stays that way it could limit the severity of today's storms.

Our storms are going to feed off the instability to the west of I-35. CAPE values are already well over 4000 j/kg and CIN is virtually gone. Clouds to the east are a non-factor for the Metro area.

[adaniel]

I'm not so sure if its possible to "feel" instability, but something about today just doesn't feel right. Its cloudy but very warm and the humidity is absolutely disgusting outside, probably the most uncomfortable its been so far this spring. Plus there's a gentle SE breeze but the clouds are moving almost due west from what I can tell. Maybe its because I've got those images of Joplin stuck in my head, but I just feel a bit concerned about today and tommorow.

You'd think that with downtown Fort Worth being hit as well as Nashville, that the evidence would disabuse anyone of the notion that they are geographically limited to where they can form. Dallas has been blasted as well a few times in the 50s.

Don't forget downtown Atlanta in 2008 during the Final Four. Plus, my parents area in Collin County, just north of Dallas, has had one touchdown and a few very near misses in the past 3 years. This is in an area with about 4-5000 people per square mile. And I lived there about 8 years before relocating to Norman without ever experiencing such a thing, so the fact that a tornado hasn't struck the in-town areas of OKC means nothing at this point.

[bandnerd]

I'm not so sure if its possible to "feel" instability, but something about today just doesn't feel right. Its cloudy but very warm and the humidity is absolutely disgusting outside, probably the most uncomfortable its been so far this spring. Plus there's a gentle SE breeze but the clouds are moving almost due west from what I can tell. Maybe its because I've got those images of Joplin stuck in my head, but I just feel a bit concerned about today and tomorrow.

I have to agree with you. I don't like the way it feels outside. It's just nasty. Guess I'll bring down the cat crates in case I have to make a quick escape to the laundry room.

[blangtang]

It was a couple years ago but I was listening to an actuary for an insurance company talk about the percentage of likelihood of a tornado directly affecting an individual who lives a life of 80 years in either Kansas or Oklahoma, and the final number was 4% over 80 years. I believe it was in some way regarding the pricing of property insurance.

It sure as hell seems like a higher chance when watching the local tv weather !!!

[Joe Kimball]

Thirded. It's the classic type of weather that usually occurs before a major tornadic storm.

[Bunty]

Tornado watch now out. Includes most of the western half of Oklahoma, but not Oklahoma County.

[Thunder]

The watch will expand as the storms evolution continues to grow and move eastward.

[venture]

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 345
NWS STORM PREDICTION CENTER NORMAN OK
230 PM CDT MON MAY 23 2011

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

WESTERN OKLAHOMA
NORTHWEST TEXAS

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 230 PM UNTIL
1000 PM CDT.

SEVERAL TORNADOES
ISOLATED INTENSE TORNADOES POSSIBLE
WIDELY SCATTERED DAMAGING WINDS
ISOLATED WIND GUSTS TO 70 MPH POSSIBLE
WIDESPREAD LARGE HAIL
HAIL TO 3.0 INCHES IN DIAMETER LIKELY

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 60 STATUTE
MILES EAST AND WEST OF A LINE FROM 25 MILES NORTHEAST OF ALVA
OKLAHOMA TO 40 MILES SOUTH SOUTHEAST OF ALTUS OKLAHOMA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU5).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

OTHER WATCH INFORMATION...CONTINUE...WW 338...WW 339...WW
340...WW 341...WW 342...WW 343...WW 344...

DISCUSSION...TCU/INCIPIENT TSTM DEVELOPMENT IS IN PROGRESS ALONG
DRYLINE IN WRN OK SW OF CSM. MODIFICATION OF 19Z OUN SOUNDING FOR
AIR MASS IMMEDIATELY E OF DRYLINE SUGGESTS THAT ENVIRONMENT IS
NEARLY UNCAPPED WITH MLCAPE OF 4000-5000 J/KG. WHILE PASSAGE OF
SHORT WAVE TROUGH TO THE NE IS NOT PARTICULARLY WELL-TIMED...STRONG
DIABATIC HEATING W OF DRYLINE SHOULD SERVE TO FOSTER AT LEAST
ISOLATED STORM DEVELOPMENT THIS AFTERNOON INTO EVENING.
INITIALLY...VERY LARGE HAIL WILL BE THE PRIMARY HAZARD WITH MATURE
SUPERCELLS GIVEN THE LOCALLY HIGHER T-TD SPREADS AND WEAK LOW-LEVEL
FLOW. THE POTENTIAL FOR TORNADOES WILL INCREASE THIS EVENING AS
LOW-LEVEL SHEAR STRENGTHENS AND LCL HEIGHTS LOWER.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
600. MEAN STORM MOTION VECTOR 27020.


TORNADO WATCH PROBABILITIES FOR WT 0345
NWS STORM PREDICTION CENTER NORMAN OK
0234 PM CDT MON MAY 23 2011

WT 0345
PROBABILITY TABLE:
PROB OF 2 OR MORE TORNADOES : 60%
PROB OF 1 OR MORE STRONG /F2-F5/ TORNADOES : 50%
PROB OF 10 OR MORE SEVERE WIND EVENTS : 30%
PROB OF 1 OR MORE WIND EVENTS >= 65 KNOTS : 30%
PROB OF 10 OR MORE SEVERE HAIL EVENTS : 80%
PROB OF 1 OR MORE HAIL EVENTS >= 2 INCHES : 90%
PROB OF 6 OR MORE COMBINED SEVERE HAIL/WIND EVENTS : 90%

&&
ATTRIBUTE TABLE:
MAX HAIL /INCHES/ : 3.0
MAX WIND GUSTS SURFACE /KNOTS/ : 60
MAX TOPS /X 100 FEET/ : 600
MEAN STORM MOTION VECTOR /DEGREES AND KNOTS/ : 27020
PARTICULARLY DANGEROUS SITUATION : NO

[Roadhawg]

Joplin, SE Kansas and NW Arkansas can't get a break from all the rain and storms this year.

[Bunty]

This significant weather advisory is for logan...noble and payne counties. At 504 pm cdt...a line of strong thunderstorms was located from 12 miles west of ceres to 6 miles northwest of cedar valley...moving east at 35 mph. Hazards include...
Hail up to the size of nickels...
Wind gusts to 50 mph...
Storm intensity is increasing and severe weather may develop rapidly. Stay alert and listen for warnings.

[Bunty]

Tornado watch now includes Lincoln and Payne Counties.

[ou48A]

When will there be a reasonable idea about how tonight’s activity will be affecting tomorrow’s storms?